When someone makes up a new word or expression to describe something, and that word or expression is just so sublime and succinct that it is quickly adopted by the mainstream or the sub-mainstream, necessitating its inclusion in the Urban Dictionary.
Beyonce 'coined the term' bootylicious to perfectly describe a rounded butt (or Big Black Ghetto Arse, depending on how you look at it). Well done Beyonce. Sorry I can't do the little dash above the 'e' in your name but Robert's explanations are crap.

Sohm-Yung Ho 'coined the term' Resident Cunt to perfectly describe... um... the resident cunt.
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